Quarterly report pursuant to Section 13 or 15(d)

Overview and Basis of Presentation - Additional Information (Detail)

v3.21.1
Overview and Basis of Presentation - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Jul. 10, 2020
Net income (loss) $ (19,452) $ (236,341)    
Accumulated deficit (743,594)   $ (724,142)  
Debt instrument debt default amount 97,500      
Debt instrument debt default principal amount 60,000      
Debt instrument debt default accrued additional fees and interest 14,200      
Revenue [Member]        
Increase in cost and expenses 2,900      
Recapitalization transaction [Member]        
Debt instrument face amount       $ 14,700
Secured Debt [Member]        
Debt Instrument debt default accrued interest amount 19,000      
Unsecured Debt [Member]        
Debt Instrument debt default accrued interest amount $ 6,000      
Senior secured convertible debentures [Member]        
Debt instrument interest rate   13.00%    
Convertible unsecured debentures [Member]        
Debt instrument interest rate   8.00%